Can I get 565cc implants?

The answer is based on what you desire. If you want a natural, full looking breast, The 385-440 cc Sientra HPs will serve you well. 565cc is a very aggressive augmentation, and will test your tissue, considering that you have a small tissue envelope (A cup). It is likely technically possible to place these large implants, but I would not recommend it. Since Sientra only provides implants to board certified plastic surgeons, you have obviously done your home work, and are in good hands.

Best Wishes

Whether or not those implants will fit will depend on not only the base width of the breast but also the amount of stretched skin in the breasts. If there is a good amount of stretched skin, then the implant will fill the pocket nicely. This is typical in women who have already had children or breastfed. If there is not much tissue laxity, then implants of that size can look constricted and unnatural. I would speak with your surgeon about your concerns and ask for a sizing session with sizers if you are uncomfortable with the recommended sizes.

Thank you for your question.
When it comes to breast augmentation, oftentimes your surgeon will allow you to "try on" different implant sizes prior to your procedure. They will have you place the implant within a bra, and then try on a tight fitting shirt to mimic the appearance of your breasts post-operatively. I recommend speaking with your plastic surgeon to discuss your concerns and for evaluation.